This is hampering businesses' ability to function, let alone grow. What's more, the fall in US consumer spending has already continued for longer than in any period since the Second World War - and Kelly reckons this will continue for at least six months.

With Kelly and virtually all his rival portfolio managers predicting that the US economy 'will remain in a mess for some time', surely this is a disaster zone for investors?

Not necessarily, according to those financial advisers who are tentatively encouraging clients to look there for recovery and growth.

Historically the US leads the world into and out of recessions.

And the stock market, which runs ahead of the real economy in predicting future gloom and subsequent recovery, has already 'priced in very bad news', says Kelly.

He points to cheap oil and Obama's commitment to boost spending. The president is 'talking big numbers in fiscal stimulus,' he says. 'There are signs in the real economy that existing measures are beginning to work.'

Kelly is hoping to profit from major changes in America's corporate landscape as those companies that survive the turmoil massively increase their market share and future revenues.